Design And Implementation Of Location System Based On Rssi In ZigBee Network

Nowadays,with the increasing importance of wireless network technology,Wi-Fi,Bluetooth,UWB,ZigBee and other wireless communication technologies have been developing rapidly.ZigBee,as a new short distance communication technology,quickly occupies the low cost,low energy consumption and low rate wireless communication market.Location technology in the wireless sensor network is also favored by various industries because of its important practical application value.Wireless location technology based on ZigBee is widely used in medical,environmental monitoring,military,industry,transportation and life fields.Based on research and analysis of existing wireless location technologies and algorithms,this thesis improves the location algorithm based on Received Signal Strength Indicator(RSSI)and builds a location system.This thesis improves the RSSI algorithm for increasing the accuracy.Firstly,the shadow model is selected as the optimal range model through analyzing empirical and theoretical models in the distance measurement.Then,the methods of Gaussian filter and Least square are used to filter and fit data for getting a more accurate range model.Finally,the positioning results are corrected by a combining method of radius distance increment and centroid calculation in the coordinate calculation stage.To build the system,a ZigBee-based wireless location network is realized based on CC2530 by adopting Z-Stack.Then a PC software is designed by Visual Studio 2012 to visualize the location information.The MATLAB tool is used for simulating,and the system is deployed in five different environments.We can see from the experiment results,that the system effectively reduces the positioning error and achieves a more accurate positioning effect.